Self-Assessment Answers: Prescribing Drugs in Neonates, Infants, Children and Adolescents

Question 1:
Starting in which year are drug manufacturers required to prove both effectiveness and safety of a drug to the FDA before marketing?

1938
1962
1966
1983

Answer: B
In 1962, the Kefauver-Harris amendments to the Food, Drug and Cosmetics Act required drug manufacturers to prove the effectiveness as well as the safety of a drug to the FDA before marketing. In addition, adverse effects must be reported to the FDA.

Question 2:
All drugs are tested in infants and children before approval.

True or False?

Answer: False
Drugs are often not tested in children or infants before approval.

Answer: True
Premature babies consist of about 60% extracellular water and over 20% intracellular water. The proportion of water decreases during growth and development. As a result, the dosing of medications that are dispersed in extracellular water can be significantly different for patients at different stages of development: premature babies, infants, children, and adults.

Question 4:
Glomerular filtration rate (GFR), a measure of the power of kidneys to clear medication, increases considerably in the first two weeks of life.

True or False?

Answer: True
Glomerular filtration rate (GFR), and medication clearance increase rapidly with age in newborn babies. As a result, babies a few days old are more prone to overdosing in the NICU than children a few weeks old.

Answer: True
Pharmacogenetics plays an important role in drug metabolism and therefore in the selection of appropriate doses for drugs. For example, the number of inherited functional genes (alleles) of CYP2C19 determines how Omeprazole (a proton pump inhibitor) is metabolized and whether the drug is able to effectively increase intragastric pH.

Question 6:
The levels of drug-metabolizing enzymes change during development before and after birth. The levels of some of these enzymes increase, some decrease, and others are not affected.

True or False?

Answer: True
Three different classes of drug-metabolizing enzymes (Classes 1, 2, and 3) are affected differently by development. For example, CYP3A7 (Class 1) activity is high before birth and decreases after birth, and CYP3A4 (Class 3) activity is very low before birth and increases after birth. The activity of SULT1A1 (Class 2) does not change significantly before and after birth.

Question 7:
A single dose of propofol, a sedative and anesthetic, in premature infants less than 10 days old can stay in the body for hours to days, much longer than in full-term infants.

True or False?

Answer: True
Premature infants less than 10 days old clear propofol more slowly than when they are over 10 days old, and they also clear the drug more slowly than full-term infants of the same age.